#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
int main()
{
    int x = 0;
    scanf("%d", &x);
    double y = 0.0;
    if (x <= 100000)
    {
        y = x * 0.1;
    }
    else if (100000 < x && x <= 200000)
    {
        y = 100000 * 0.1 + (x - 100000) * 0.075;
    }
    else
    {
        y = 100000 * 0.1 + 100000 * 0.075 + (x - 200000) * 0.05;
    }
    printf("%.2lf\n", y);
    return 0;
}